I think both structural-functional theory as well as conflict theory makes strong points about urban growth and decline. When it comes to urban growth, structural-functional theory seems to be bit more accurate because it says that the urbanization occurs in a predictable way – with different patterns followed in different growth of a city. One example of a pattern is when a small area starts to play a role of economic development such area grows outward from a small place to a bigger city. According to them, the urban growth happens when there is a natural competition among economic entities the eventually lead to more demand of people and the products. On the other hand, the conflict theory claims that there is neither a pattern nor anything natural about urban growth. But conflict theory does seem to make a better point when it comes to discussing urban decline because it says that urban decline happens as a result of government providing subsidies to help grow suburbs, which seems to be true. When suburbanization happens, people move from dangerous cities to safe as well as economically prosperous suburbs. The structural-functional theory doesn’t make much comment about urban decline except that it happens in a predictable way.
Louis Wirth made statements about urbanization resulting in the greater size, heterogeneity and density of urban living affecting our everyday lives. I think there is some truth in that although greater size can help economic prosperity, it does affect the moral fabrication of our everyday life. More people feel stranger to each other than if they were living in a non-urban setting. Different groups of people come to city and form heterogeneity that that might break down social interaction and thus the rigid social structure but can also potentially form their own groups of homogenous social clubs, etc.